How do you "tune up" a hard-to-start Craftsman 18" chainsaw

You're joking right?
CORDED:
The reason a chain saw can't use a power cord is that it would need to be
hundreds upon hundreds of feet long and would be impossible to drag through
the chaparral without catching on scores of bushes, rocks, and trees.
BATTERY:
The reason a chain saw can't use a battery is that it would die after
felling only a few trees and cutting up the limbs. We'd spend more time
waiting for it to charge than cutting.
FOUR STROKE:
The reason most chain saws aren't four strokes, as far as I can tell, is
that four strokes without oil pumps can't be placed in all the positions
that a chain saw needs to be without spilling oil into the cylinder.
TWO STROKE:
The reason most chain saws are two strokes, I presume, is that is less
expensive than a oil-pump driven four stroke and the two stroke works in
any position.
BTW, if there are good four-stroke chain saws on the market, let me know
which you prefer.

CORDED:
The reason a chain saw can't use a power cord is that it would need to
be
hundreds upon hundreds of feet long and would be impossible to drag
through
the chaparral without catching on scores of bushes, rocks, and trees.
CY: Even with a portable generator, still not really convenient.
BATTERY:
The reason a chain saw can't use a battery is that it would die after
felling only a few trees and cutting up the limbs. We'd spend more
time
waiting for it to charge than cutting.
CY: Need the new Nuclear Power Batteries. They are sold out of North
Korea, on Ebay. Don't want the Iranian Nuclear Power Batteries, they
sometimes explode.
FOUR STROKE:
The reason most chain saws aren't four strokes, as far as I can tell,
is
that four strokes without oil pumps can't be placed in all the
positions
that a chain saw needs to be without spilling oil into the cylinder.
CY: And they are heavier. The used to be made, for felling trees. When
one knows the saw operation is always going to be in the same
position. They were operated by two men.
TWO STROKE:
The reason most chain saws are two strokes, I presume, is that is less
expensive than a oil-pump driven four stroke and the two stroke works
in
any position.
CY: Also, the two stroke fires on every piston stroke, so the HP to
weight ratio is much higher.
BTW, if there are good four-stroke chain saws on the market, let me
know
which you prefer.
CY: I havn't looked, but they are likely out of the home owner price
range.

Where weight counts, as in a chainsaw, the two stroke cycle gives you
power on every stroke where the 4 stroke cycle is only on every other
stroke. That is really why. But to make a "run in any position" four
stroke would increase the complexity.

The poster confused me a little (nothing permanent).
The lobe on the crank/cam still needs to turn four times... thus four
strokes.
I've always called it: intake, compression, power and exhaust.
Counting combustion the same as the power stroke.

Am I mistaken, or does a "four stroke" fire on every other rotation? The
ignition spark powers the crank down from a few degrees BTDC for power with
all valves closed, and the upcoming piston pushes out the exhaust with the
exhaust valve open. When it reaches TDC, the downward traveling piston
sucks in gas through the open/opening intake valve, and when it reaches its
designated firing degree BTDC, it fires. Every other stroke.
With a two stroke, the spark plug fires every rotation, with the intake and
exhaust being achieved by a porting system routing gas and exhaust on
different sides of the piston.
Class?
Class?
Steve
Heart surgery pending?
Read up and prepare.
Learn how to care for a friend.
http://cabgbypasssurgery.com

No. Spark happens, piston travels to bottom, on the upstroke, the exhaust
valve opens, piston comes up, pushes out spent gas, at TDC, intake valve
opens, piston drops pulling in air, comes up on compression stroke, and a
few degrees BTDC, fires again. One spark per two full revolutions of crank.
Steve

The four strokes of a four stroke engine in living ASCII art
http://www.repairfaq.org/samnew/lmfaq/lmtfsofse.htm
I still call the compression stroke the power stroke --even if firing
at BTDC or TDC. I think we get it.

Thanks for the link, that's fun.
If you want to talk with other mechanics, it would be wise to call the
compression and power strokes different things. The compression stroke
is the one before the power stroke.
Intake
Compression
Power
Exhaust
(in that order)

Worth noting. There are actually two sparks, per fire. One spark is at
TDC when the gasses are compressed. The second spark is also at TDC at
the end of the exhaust stroke. The second spark is wasted, but does no
damage.

Simple small four stroke engines (lawnmowers etc.) spark every crank
revolution. The spark is usually triggered by the crankshaft on small
four stroke engines. Larger four stroke engines (automobiles) spark
every second crank revolution per cylinder. The spark is usually triggered
by the camshaft on large four stroke engines. The camshaft rotates
at half the speed of the crankshaft.

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